The present invention relates to a means for height adjustment of folding doors, and in particular to a pivot pin assembly for use therefor. Pivot pin assemblies are located on the inside of the folding door and provide the vertical alignment necessary for proper operation during opening and closing of the folding door.
Folding doors have long been used in situations where limited "swing" area for a door is available or desired for closets and the like. Folding doors include at least one pair of guide and pivot doors. The front of the folding door may be prefinished or improved and may include a knobbed or flanged handle.
The framework of the folding door, including the rails stiles, hinges, and corner blocks, are typically exposed at the back of the guide and pivot doors. The rails are horizontal members to which are attached the corner blocks containing the guide and pivot assemblies. Additional corner blocks are located where the hinges connect the guide and pivot doors. The stiles are vertical members to which is attached the handle. Stiffening members may be provided on the pivot door for added structural integrity.
Today, folding doors are typically assembled within a factory and often installed by an installer or by the homeowner. During installation, the folding doors are to be aligned to be plumb with the door frame of the closet. If two pairs of guide and pivot doors are used, they must be installed such that they are horizontally and vertically aligned with one another as well.
For horizontal alignment with the upper door frame, the top and/or bottom track bracket is adjusted. The vertical alignment of the folding door is usually accomplished by adjusting only the bottom pivot pin. The pin may either be contained in a housing or directly inserted within one of the cavities of the bottom, inside corner block. The adjustment is typically done with a thin wrench to be inserted beneath the lower edge of the door, and is an awkward procedure because of the corner block's position inside the closet. An adjustment or lock nut is sometimes used to maintain the height of the door after installation and alignment. The difficulty in using a wrench for the height adjustment is compounded by the fact that it involves a certain amount of trial and error.
Another way of vertically adjusting the doors is by the use of a lock nut with a threaded pivot pin having a slotted head. Thus, a screwdriver may be used to adjust the pivot pins instead of a wrench. However, whether the pivot pin is adjusted by a screwdriver or a wrench, a "ratchet" effect occurs over time, as the pivot pin is "torqued" by the swinging open and close of the door. The pin is rotated at a point of contact of its bottom end with the track bracket. The lock nut is rotated by the pivoting of the pin and becomes loosened. The ratchet effect occurs from the weight of the door that is supported by the pivot pin, which causes the pin to only adjust downward. Thus, misalignment of the door results as the pin is rotated and no longer held in the proper position by the lock nut.
In view of the foregoing, a need exists for an improved pivot pin adjustment mechanism that overcomes the problems mentioned.